public static function pageNav($total_num, $on_page, $diapason, $url){



    if(isset($_GET['start'])){



      $start=abs(intval($_GET['start']));



    } else {



      $start=0;



    }



    $max_page=ceil($total_num/$on_page);



    $current_page=round(($start/$on_page), 0);



    if(($current_page-$diapason)>-1) echo'<a href="' . $url . '">1...</a>&nbsp;&nbsp;'; 



    for($i=-($diapason-1);$i<$diapason;$i++){



    $go=$current_page+$i;



    if($go<0||($go+1)>$max_page) continue;



    if($go==$current_page){



        echo'<b>[' . ($go+1) . ']</b>&nbsp;&nbsp;';



        continue;



    }



    echo'<a href="' . $url . ((substr_count($url, '?')>0)?'&start=':'?start=') . ($go*$on_page) . '">' . ($go+1) . '</a>&nbsp;&nbsp;';



    }



    if(($current_page+$diapason)<$max_page) echo'<a href="' . $url . ((substr_count($url, '?')>0)?'&start=':'?start=') . ($max_page*$on_page) . '">...' . $max_page . '</a>&nbsp;&nbsp;'; 



  }